The superior vena cava (SVC) is a large vein that carries deoxygenated blood from the head, neck, arms, and upper chest back to the right atrium of the heart. It is formed by the junction of the right and left brachiocephalic veins behind the first rib. On echocardiography, the SVC can be partially visualized, particularly from the suprasternal and subcostal windows, and its entry into the right atrium is seen. SVC syndrome — obstruction of the SVC by tumor, thrombus, or external compression — can cause facial swelling, distended neck veins, and shortness of breath. While CT or MRI provides comprehensive SVC evaluation, echocardiography can identify associated findings such as right atrial dilation, masses, or pericardial effusion.
Sonography Term